These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Prince Robot IV seems to be becoming one due to how hilarious and utterly weird the character is.
Izabel, if fanart is anything to go by.
It Will Never Catch On: The author himself joked that, due to how non-main stream the comic is ("an original fantasy book with no superheroes, two non-white leads and an opening chapter featuring graphic robot sex"), he thought the book would be cancelled by issue 3.
Nightmare Fuel: Marko losing it and trying to slaughter a group of soldiers after he mistakenly believes they hurt Alana.
The gas we see in a flashback that causes it's victims to explode. Prince Robot had to watch a poor medic who got caught in it without a gas mask burst apart at the seams, splattering blood all over him.
Signature Scene: Marko and Alana's post-sex argument in issue 11 seems to be frequently cited as "Saga in a nutshell". Not surprising given that it has some of the comic's funniest lines.
Squick: The series isn't afraid to engage in this from time to time.
The giant that Marko and Klara encounter in issue 7 and 8 has a pair of gigantic, prominent, and hairy testicles. This is not figurative. They are literal huge dangling monster balls that take up maybe twenty percent of a splash-page. Vaughan's script for his first appearance has been released, showing that Vaughan actually apologized to Staples for making her draw it.
The Will's preferred means of attack seems to be bisecting people. The Lying Cat has been shown eating the skin off a victim's face.
The close up of Prince Robot's wife giving birth.
Marko cutting his new baby's umbillical cord... with his teeth.
The Brand's visit to The Will in the hospital in issue 18; it's revealed that they're siblings, and that they had been estranged for years. Her name is also Sophie, the name he gave to the young girl he rescued.